Preserving the Earth's Biodiversity
What must we consider?

What is biodiversity?

Variety of living organisms
The simple measure is to count the number of species (Species richness)
- is this enough? what if each species only had a few individuals?
Must also look at representation. How evenly distributed are the organisms across all species?
Other forms of diversity matter: genetic diversity within a species, ecosystem diversity (habitats)

How much diversity is out there?

Approximately 1.5 million named and categorized species (bacteria, plants, animals, etc.)
Estimates range between 14 and 114 million total species!
Where and what are all the undiscovered species?

Is biodiversity valuable?

Instrumental Value = direct $ value to humans (fish, lumber, etc.)
- makes conservation important and easier when $ is apparent
Intrinsic Value = value for its own sake (pandas)
- more philosophical question of conservation
- makes it harder to conserve
Ecosystem Services = what the environment does for us for free
- Estimates of the value of "natural capital" are $38 trillion/year!
- Total global GNP is only ~$18 trillion
- Clean air, water, soil, pollination, food, fiber, lumber, nutrient cycling, decomposition, medicine, pest control, recreation, genetic diversity, etc.
- Protecting biodiversity then protects the investment in the environment
- Can we afford to replace?

What is extinction?

Death of a species - when the last member dies
Background Extinction = natural extinction through evolution. Fossil records indicate the rate is about 1 mammal per 400 years and 1 bird per 800 years.
Mass Extinction = large-scale die off of species. Fast in terms of geologic time. 5 prior episodes, last was the dinosaurs.
Current extinction rates indicate that 20-25 mammals have gone extinct in the last 100 years
Are we in a mass extinction? Did we cause it?
- There have been ~500 extinctions of plants, animals, birds, etc. in North America since colonization
- 1/3 of North American species are threatened or endangered
- Globally, there have been over 700 animal extinctions and 90 plant extinctions since 1500
- 24% of all mammals are threatened - and mammals are a well studied group. What about insects, fungi, bacteria, or fish?
Endangered Species = in imminent danger of extinction throughout all or most of its range
- If we can help declining species in time, perhaps we can prevent extinction
- US Engangered Species Act
  - Lists species and provides protection
  - Protects critical habitat (controversial because it conflicts with private property rights)
  - Detailed recovery plan
  - Currently 1,272 speices listed (threatened and engangered)
    - 14 have been delisted, 9 have gone extinct
  - Program suffers from complete lack of data, limited funding, and private property rights debate

What characteristics are common among endangered/extinct speies?

Small Range - the entire species is only found in limited areas
Large Territory - individuals cover lots of ground (more conflicts possible)
Endemic to an island - evolved in isolation, very specialized
Low reproductive rates - populations cannot rebound quickly
Specialized feeding habits - eat limited things
High on the food chain - impacted by everything below it (also conflicts with humans)

Where is the most biodiversity? Where are the problem areas?

Biodiversity is everywhere and everywhere is important
However, some areas contain more species and more unique (endemic) species
Tropics, coastal areas, islands
nIn tropical rainforests, biodiversity his highest. For example: 43 species of ant on 1 tree, 300 species of tree in 2.5 acres, 10,000 species of insects on 1 tree.
Developing countries have lots of diversity and also have big impacts. Why?

Global Biodiversity "Hot-spots"

image from nature.com

What are the reasons for biodiversity loss?
HIPPO

Habitat Loss - conversion to other things (agriculture), fragmentation, simplification, intrusion
Invasive Species - biotic pollution
Pollution - acid rain, global warming, eutrophication, toxic spills, etc.
Population - human overpopulation (again)
Over exploitation - commercial harvest (fish), pet trade, poverty, greed, poor mangement

How can we protect biodiversity?

Conserve habitats (in situ conservation)
- stop habitat loss
- protect reserves/preserves
- connect critical areas
- Single large reserve or several small?
- US has a good system
- 10% of land area is ideal
Restoration ecology (in situ)
- Return area to natural states, reintroduce native speices
- Expensive and time consuming
- US has good track record: deer, otters, elk, falcons, prairie habitats
Zoos, Aquariums, Botanical Gardens, Seed Banks (ex situ)
- Captive breeding & reintroduction
- Expensive, doesn't work for all species

Who is protecting biodiverity?

IUCN (World Conservation Union)
- maintains the Red List (11,000+ globally endangered species)
- TRAFFIC database (Trade Records Analysis for Flora and Fauna in International Commerce)
World Wildlife Federation
- fund raising for research and awarness

There are others - look them up

What legal strategies are in place?
n
Endangered Species Act (ESA)

n1982 amendment to ESA allows landowner to“take” an endangered species if it does not interfere with the recovery plan of the species
nGreat deal of controversy around this provision

CITES – Convention on International Trade in Endangered Species of Wild Flora and Fauna (160 nations)